153 research outputs found

    Demographic effects of aggregation in the presence of a component Allee effect

    Full text link
    Intraspecific interactions are key drivers of population dynamics because they establish relations between individual fitness and population density. The component Allee effect is defined as a positive correlation between any fitness component of a focal organism and population density, and it can lead to positive density dependence in the population per capita growth rate. The spatial structure is key to determining whether and to which extent a component Allee effect will manifest at the demographic level because it determines how individuals interact with one another. However, existing spatial models to study the Allee effect impose a fixed spatial structure, which limits our understanding of how a component Allee effect and the spatial dynamics jointly determine the existence of demographic Allee effects. To fill this gap, we introduce a spatially-explicit theoretical framework where spatial structure and population dynamics are emergent properties of the individual-level demographic rates. Depending on the intensity of the individual processes the population exhibits a variety of spatial patterns that determine the demographic-level by-products of an existing individual-level component Allee effect. We find that aggregation increases population abundance and allows populations to survive in harsher environments and at lower global population densities when compared with uniformly distributed organisms. Moreover, aggregation can prevent the component Allee effect from manifesting at the population level or restrict it to the level of each independent group. These results provide a mechanistic understanding of how component Allee effects operate for different spatial population structures and show at the population level. Our results contribute to better understanding population dynamics in the presence of Allee effects and can potentially inform population management strategies

    Psychological Factors Related to Fibromyalgia Syndrome Phenomenon

    Get PDF
    Fibromyalgia is a chronic rheumatic syndrome characterized mainly by diffuse musculoskeletal pain. Its diagnosis is clinical and the presence of 15 to 18 tender specific painful body sites (tender points), with no specific laboratory alterations. It is often associated with other symptoms such as constant fatigue, swelling, morning stiffness, difficulty in memorizing and concentrating, mood swings, anxiety, and depression, among others. This condition mainly affects women, bringing a considerable negative impact on carriers. Pain perception is the result of multiple factors: biological, social, and psychological. This study sought through qualitative research to recognize the psychosocial factors related to fibromyalgia, as well as identify the possible meanings to suffering, seeking to contribute to elucidate the psychogenic phenomena related to the pain of Fibromyalgia Syndrome. Finally, to analyze if patients who are undergoing psychotherapy follow-up benefit from the symptoms caused by chronic pain of fibromyalgia. The result is divided into three categories: Implications of the diagnosis in social relations, repercussions of the diagnosis on the interviewees\u27 quality of life, and psycho-affective symptoms experienced by the interviewed fibromyalgia patients. According to the research, it was observed physical limitation, adding severe pain, memory impairment, concentration, excessive fatigue, resulting in psychic suffering characterized as guilt, frustration, depression, anxiety, and self-image affected. In this study, ten female patients with a mean age of 40.2 years were interviewed, of which 30% are undergoing psychological follow-up, which resulted in greater acceptance of their comorbidity and coping with it

    MACROECOLOGIA, BIOGEOGRAFIA E ÁREAS PRIORITÁRIAS PARA CONSERVAÇÃO NO CERRADO

    Get PDF
    revista vol 13 nÂș 3.indd HĂĄ consenso entre os cientistas de que a hĂĄ atualmente uma “crise da biodiversidade”, resultado da constante e intensa perda de habitat natural causada pela expansĂŁo da ocupação. Como a biologia da conservação tem sido muitas vezes reconhecida como uma ciĂȘncia da crise, ela deve fornecer informaçÔes capazes de mediar, de forma mais cientĂ­fica possĂ­vel, as tomadas de decisĂŁo que sĂŁo necessĂĄrias. Dentre estas, uma das mais importantes Ă© indicar regiĂ”es prioritĂĄrias para a conservação, jĂĄ que por motivos Ăłbvios nĂŁo Ă© possĂ­vel preservar todos os ecossistemas por inteiro. Nesse contexto, recentemente sugeriu-se que a aplicação de princĂ­pios, teorias e anĂĄlises provenientes da biogeografia e da macroecologia seriam importantes na Biologia da Conservação, formalizando uma abordagem que tem sido denominada “Biogeografia da Conservação”. Assim, o objetivo deste artigo Ă© discutir e revisar esses componentes da biogeografia da conservação, utilizando uma abordagem macroecolĂłgica para desenvolver e aplicar mĂ©todos de planejamento sistemĂĄtico em conservação, utilizando o bioma Cerrado como um modelo de estudo. Foram discutidos inicialmente os padrĂ”es de riqueza e diversidade beta e, em um segundo momento, como esses padrĂ”es podem ser correlacionados Ă  ocupação humana do Bioma. Essa relação Ă© fundamental para subsidiar a aplicação de modelos de planejamento sistemĂĄtico de conservação em escala regional (anĂĄlises de insubstituibilidade, complementaridade e de lacunas). É preciso considerar tambĂ©m que hĂĄ sĂ©rias falhas de conhecimento sobre os padrĂ”es de biodiversidade na regiĂŁo e que a escolha de grupos indicadores pode ser importante para minimizar problemas gerados pela falta de conhecimento. Assim, essa abordagem Ă© interessante em um cenĂĄrio de grandes incertezas (ausĂȘncia de dados detalhados) e de rĂĄpida transformação da paisagem, possibilitando a otimização de estudos em grandes escalas e depois transferir os resultados para escalas espaciais mais locais e realmente relevantes para a conservação. Nessas regiĂ”es, podem ser realizados, em um segundo momento, estudos mais detalhados a fim de avaliar padrĂ”es de viabilidade populacional, fragmentação de habitat e regiĂ”es potenciais de manutenção da diversidade genĂ©tica

    Bullying escolar: um fenĂŽmeno multifacetado

    Get PDF
    School bullying can involve children in different ways, making them play different roles, among them, victims, bullies and bully-victims. The aim of this study was to describe how bullying occurs in high social vulnerability schools of FlorianĂłpolis metropolitan area and the roles played by students in this phenomenon. Overall, 409 children and adolescents from the 3rd to 5th grades and of two public elementary schools aged 8-16 years (X = 11.14) participated in this study. As a tool, the Olweus Questionnaire adapted to the Brazilian population was used. For data analysis, descriptive statistics and inferential statistics were applied by the Mann Whitney and Kruskal Wallis tests. As for results, 29.8% of boys and 40.5% of girls reported being victims; 32.3% of boys and 24.6% of girls reported being bullies. Victims were the most willing to help a colleague who is suffering from bullying (X = 1.54; p> 0.001), even if they do not know the victims (X = 1.57; p> 0.004). Bullies are differentiated from the group that does not participate (X = 1.73) and the group of victims (X = 2.34), being those who felt less alone (x = 1.47; p> 0.001). It was concluded that the information obtained in this study is indispensable in the search for alternatives to reduce school bullying. The strengthening of relations between school and students and a better preparation of teachers and school staff are extremely necessary to try to minimize the effects of risk factors to which these children are exposed and consequently violence at school.O bullying escolar pode envolver crianças de diferentes maneiras, fazendo com que essas assumam papĂ©is diferenciados. Dentre estes, tĂȘm-se vĂ­timas, agressores e vĂ­timas-agressoras. O objetivo deste estudo foi descrever como ocorre o bullying em escolas de alta vulnerabilidade social da Grande FlorianĂłpolis e os papĂ©is assumidos pelos alunos nesse fenĂŽmeno. Quanto ao mĂ©todo, participaram 409 crianças e adolescentes do terceiro ao quinto ano e da quarta Ă  sexta sĂ©rie do ensino fundamental, de duas escolas pĂșblicas municipais, com idades entre 8 e 16 anos (X=11,14). Como instrumento, utilizou-se o QuestionĂĄrio de Olweus adaptado Ă  população brasileira. Para a anĂĄlise dos dados, empregaram-se a estatĂ­stica descritiva e estatĂ­stica inferencial por meio dos testes Mann Whitney e Kruskal Wallis. Quanto aos resultados, 29,8% dos meninos e 40,5% das meninas relataram terem sido vĂ­timas; jĂĄ 32,3% dos meninos e 24,6% das meninas relataram terem sido agressores. As vĂ­timas foram as que se mostraram mais dispostas a ajudar como podem um colega que esteja sofrendo agressĂŁo (X=1,54; p>0,001), mesmo que nĂŁo o conheçam (X=1,57; p>0,004). Em contrapartida, os agressores se diferenciaram do grupo que nĂŁo participa (X=1,73) e do grupo das vĂ­timas (X=2,34), sendo aqueles que menos se sentiram sozinhos (X=1,47; p>0,001). Concluiu-se que as informaçÔes obtidas neste estudo sĂŁo indispensĂĄveis na busca de alternativas para redução do bullying escolar. O fortalecimento das relaçÔes entre escola e alunos, e um maior preparo dos professores e funcionĂĄrios sĂŁo extremamente necessĂĄrios para tentar minimizar os efeitos dos fatores de risco a que essas crianças estĂŁo expostas e consequentemente a violĂȘncia na escola.CAPES - Proc. nÂș 0815/14-4CIEC - Centro de Investigação em Estudos da Criança, IE, UMinho (UI 317 da FCT)Projeto EstratĂ©gico da FCT: UID/CED/00317/201

    [Covid-19 in the Northeast of Brazil: from lockdown to the relaxation of social distancing measures].

    Get PDF
    Even in the period when the Covid-19 pandemic was on the rise in the Northeast of Brazil, the relaxation of social distancing measures was introduced. The scope of the study is to assess, in the light of the epidemiological-sanitary situation in the region, the suitability of relaxation of social distancing measures. Based on the WHO guidelines for relaxation of social distancing, operational indicators were created and analyzed for each guideline in the context of the Northeast. To analyze the behavior of the epidemic, according to selected indicators, Joinpoint trend analysis techniques, heat maps, rate ratios and time trends between capitals and the state interior were compared. The weekly growth peak of the epidemic occurred in May-July 2020 (epidemiological weeks 19 to 31). In most capitals, there was no simultaneous downward trend in the number of cases and deaths in the 14 days prior to flexibilization. In all states the number of tests performed was insufficient. In epidemiological week 24, the state percentages of ICU/Covid-19 bed occupancy were close to or above 70%. The epidemiological situation of the nine Northeastern state capitals analyzed here did not meet criteria and parameters recommended by the World Health Organization for the relaxation of social distancing measures

    Pervasive gaps in Amazonian ecological research

    Get PDF

    Pervasive gaps in Amazonian ecological research

    Get PDF
    Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio

    Mitochondrial physiology

    Get PDF
    As the knowledge base and importance of mitochondrial physiology to evolution, health and disease expands, the necessity for harmonizing the terminology concerning mitochondrial respiratory states and rates has become increasingly apparent. The chemiosmotic theory establishes the mechanism of energy transformation and coupling in oxidative phosphorylation. The unifying concept of the protonmotive force provides the framework for developing a consistent theoretical foundation of mitochondrial physiology and bioenergetics. We follow the latest SI guidelines and those of the International Union of Pure and Applied Chemistry (IUPAC) on terminology in physical chemistry, extended by considerations of open systems and thermodynamics of irreversible processes. The concept-driven constructive terminology incorporates the meaning of each quantity and aligns concepts and symbols with the nomenclature of classical bioenergetics. We endeavour to provide a balanced view of mitochondrial respiratory control and a critical discussion on reporting data of mitochondrial respiration in terms of metabolic flows and fluxes. Uniform standards for evaluation of respiratory states and rates will ultimately contribute to reproducibility between laboratories and thus support the development of data repositories of mitochondrial respiratory function in species, tissues, and cells. Clarity of concept and consistency of nomenclature facilitate effective transdisciplinary communication, education, and ultimately further discovery

    Author Correction:A consensus protocol for functional connectivity analysis in the rat brain

    Get PDF

    Mitochondrial physiology

    Get PDF
    As the knowledge base and importance of mitochondrial physiology to evolution, health and disease expands, the necessity for harmonizing the terminology concerning mitochondrial respiratory states and rates has become increasingly apparent. The chemiosmotic theory establishes the mechanism of energy transformation and coupling in oxidative phosphorylation. The unifying concept of the protonmotive force provides the framework for developing a consistent theoretical foundation of mitochondrial physiology and bioenergetics. We follow the latest SI guidelines and those of the International Union of Pure and Applied Chemistry (IUPAC) on terminology in physical chemistry, extended by considerations of open systems and thermodynamics of irreversible processes. The concept-driven constructive terminology incorporates the meaning of each quantity and aligns concepts and symbols with the nomenclature of classical bioenergetics. We endeavour to provide a balanced view of mitochondrial respiratory control and a critical discussion on reporting data of mitochondrial respiration in terms of metabolic flows and fluxes. Uniform standards for evaluation of respiratory states and rates will ultimately contribute to reproducibility between laboratories and thus support the development of data repositories of mitochondrial respiratory function in species, tissues, and cells. Clarity of concept and consistency of nomenclature facilitate effective transdisciplinary communication, education, and ultimately further discovery
    • 

    corecore